1. Field of the Invention
The invention generally relates to an optical apparatus, and more particularly, to a fundus image detection apparatus.
2. Description of Related Art
Eyes are the window to the soul, and the health of eyes is crucial to each one of us. Existing eye inspection apparatuses include pneuma-tonometers, refractometers, and fundus cameras. A fundus camera is an image detection apparatus used for inspecting the fundus of an eye, and which is used for detecting any degeneration on the fundus tissue, such as retina detachment. Besides, because blood vessels can be observed by looking at the fundus, fundus inspection can help to diagnose eye diseases. Especially, retina detachment (for example, retinal degeneration caused by diabetes) can be tracked through regular fundus inspections.
Because the fundus of an eye forms a cambered concave, the fundus image obtained by a fundus image detection apparatus comes with pincushion distortion. The pincushion distortion may cumber the doctor's diagnosis regarding the degeneration of the fundus tissue. To diminish the pincushion distortion on a fundus image, a conventional fundus image detection apparatus is usually disposed with special aspherical lenses. However, these aspherical lenses are very costly therefore are not suitable for low-cost handheld fundus image detection apparatuses.